// tipsy, facebook style tooltips for jquery
// version 1.0.0a
// (c) 2008-2010 jason frame [jason@onehackoranother.com]
// released under the MIT license

(function($) {

	function maybeCall(thing, ctx) {
		return ( typeof thing == 'function') ? (thing.call(ctx)) : thing;
	};

	function Tipsy(element, options) {
		this.$element = $(element);
		this.options = options;
		this.enabled = true;
		this.fixTitle();
	};

	Tipsy.prototype = {
		show : function() {
			var title = this.getTitle();
			if(title && this.enabled) {
				var $tip = this.tip();

				$tip.find('.tipsy-inner')[this.options.html ? 'html' : 'text'](title);
				$tip[0].className = 'tipsy';
				// reset classname in case of dynamic gravity
				$tip.remove().css({top: 0, left: 0, visibility: 'hidden', display: 'block'}).prependTo(document.body);

				var pos = $.extend({}, this.$element.offset(), {
					width : this.$element[0].offsetWidth,
					height : this.$element[0].offsetHeight
				});

				var actualWidth = $tip[0].offsetWidth, actualHeight = $tip[0].offsetHeight, gravity = maybeCall(this.options.gravity, this.$element[0]);

				var tp;
				var mp;
				switch (gravity.charAt(0)) {
					case 'n':
						tp = {
							top : pos.top + pos.height + this.options.offset,
							left : pos.left + pos.width / 2 - actualWidth / 2
						};
						mp = {
							top : 15,
							left : -actualWidth / 2
						};
						break;
					case 's':
						tp = {
							top : pos.top - actualHeight - this.options.offset,
							left : pos.left + pos.width / 2 - actualWidth / 2
						};
						mp = {
							top : -actualHeight - 15,
							left : -actualWidth / 2
						};
						break;
					case 'e':
						tp = {
							top : pos.top + pos.height / 2 - actualHeight / 2,
							left : pos.left - actualWidth - this.options.offset
						};
						mp = {
							top : -actualHeight / 2,
							left : -12 - actualWidth
						};
						break;
					case 'w':
						tp = {
							top : pos.top + pos.height / 2 - actualHeight / 2,
							left : pos.left + pos.width + this.options.offset
						};
						mp = {
							top : -actualHeight / 2,
							left : 12
						};
						break
				}

				if(gravity.length == 2) {
					if(gravity.charAt(1) == 'w') {
						tp.left = pos.left + pos.width / 2 - 15;
					} else {
						tp.left = pos.left + pos.width / 2 - actualWidth + 15;
					}
				}

				if(this.options.followMouse) {
					$(document).bind('mousemove', function(e) {
						var x = e.pageX + mp.left, y = e.pageY + mp.top;
						$tip.css({
							left : x,
							top : y
						})
					})
				}

				$tip.css(tp).addClass('tipsy-' + gravity);
				$tip.find('.tipsy-arrow')[0].className = 'tipsy-arrow tipsy-arrow-' + gravity.charAt(0);
				if(this.options.className) {
					$tip.addClass(maybeCall(this.options.className, this.$element[0]));
				}

				if(this.options.fade) {
					$tip.stop().css({opacity: 0, display: 'block', visibility: 'visible'}).animate({
						opacity : this.options.opacity
					});
				} else {
					$tip.css({
						visibility : 'visible',
						opacity : this.options.opacity
					});
				}
			}
		},
		hide : function() {
			if(this.options.fade) {
				this.tip().stop().fadeOut(function() { $(this).remove();
				});
			} else {
				this.tip().remove();
			}
		},
		fixTitle : function() {
			var $e = this.$element;
			if($e.attr('title') || typeof ($e.attr('original-title')) != 'string') {
				$e.attr('original-title', $e.attr('title') || '').removeAttr('title');
			}
		},
		getTitle : function() {
			var title, $e = this.$element, o = this.options;
			this.fixTitle();
			var title, o = this.options;
			if( typeof o.title == 'string') {
				title = $e.attr(o.title == 'title' ? 'original-title' : o.title);
			} else if( typeof o.title == 'function') {
				title = o.title.call($e[0]);
			}
			title = ('' + title).replace(/(^\s*|\s*$)/, "");
			return title || o.fallback;
		},
		setTitle : function(title) {
			this.options.fallback = title
		},
		tip : function() {
			if(!this.$tip) {
				this.$tip = $('<div class="tipsy"></div>').html('<div class="tipsy-arrow"></div><div class="tipsy-inner"></div>');
			}
			return this.$tip;
		},
		validate : function() {
			if(!this.$element[0].parentNode) {
				this.hide();
				this.$element = null;
				this.options = null;
			}
		},
		enable : function() {
			this.enabled = true;
		},
		disable : function() {
			this.enabled = false;
		},
		toggleEnabled : function() {
			this.enabled = !this.enabled;
		}
	};

	$.fn.tipsy = function(options) {
		if(options === true) {
			return this.data('tipsy');
		} else if( typeof options == 'string') {
			var tipsy = this.data('tipsy');
			if(tipsy)
				tipsy[options](arguments[1]);
			return this;
		}
		options = $.extend({}, $.fn.tipsy.defaults, options);

		function get(ele) {
			var tipsy = $.data(ele, 'tipsy');
			if(!tipsy) {
				tipsy = new Tipsy(ele, $.fn.tipsy.elementOptions(ele, options));
				$.data(ele, 'tipsy', tipsy);
			}
			return tipsy;
		}

		function enter() {
			var tipsy = get(this);
			tipsy.hoverState = 'in';
			if(options.delayIn == 0) {
				tipsy.show();
			} else {
				tipsy.fixTitle();
				setTimeout(function() {
					if(tipsy.hoverState == 'in')
						tipsy.show();
				}, options.delayIn);
			}
		};

		function leave() {
			var tipsy = get(this);
			tipsy.hoverState = 'out';
			if(options.delayOut == 0) {
				tipsy.hide();
			} else {
				setTimeout(function() {
					if(tipsy.hoverState == 'out')
						tipsy.hide();
				}, options.delayOut);
			}
		};

		if(!options.live)
			this.each(function() { get(this);
			});
		if(options.trigger != 'manual') {
			var binder = options.live ? 'live' : 'bind', eventIn = options.trigger == 'hover' ? 'mouseenter' : 'focus', eventOut = options.trigger == 'hover' ? 'mouseleave' : 'blur';
			this[binder](eventIn, enter)[binder](eventOut, leave);
		}

		return this;

	};
	$.fn.tipsy.defaults = {
		className : null,
		delayIn : 0,
		delayOut : 0,
		fade : false,
		fallback : '',
		gravity : 'n',
		html : false,
		live : false,
		offset : 0,
		opacity : 0.8,
		title : 'title',
		trigger : 'hover'
	};

	// Overwrite this method to provide options on a per-element basis.
	// For example, you could store the gravity in a 'tipsy-gravity' attribute:
	// return $.extend({}, options, {gravity: $(ele).attr('tipsy-gravity') || 'n' });
	// (remember - do not modify 'options' in place!)
	$.fn.tipsy.elementOptions = function(ele, options) {
		return $.metadata ? $.extend({}, options, $(ele).metadata()) : options;
	};
	$.fn.tipsy.autoNS = function() {
		return $(this).offset().top > ($(document).scrollTop() + $(window).height() / 2) ? 's' : 'n';
	};
	$.fn.tipsy.autoWE = function() {
		return $(this).offset().left > ($(document).scrollLeft() + $(window).width() / 2) ? 'e' : 'w';
	};
	/**
	 * yields a closure of the supplied parameters, producing a function that takes
	 * no arguments and is suitable for use as an autogravity function like so:
	 *
	 * @param margin (int) - distance from the viewable region edge that an
	 *        element should be before setting its tooltip's gravity to be away
	 *        from that edge.
	 * @param prefer (string, e.g. 'n', 'sw', 'w') - the direction to prefer
	 *        if there are no viewable region edges effecting the tooltip's
	 *        gravity. It will try to vary from this minimally, for example,
	 *        if 'sw' is preferred and an element is near the right viewable
	 *        region edge, but not the top edge, it will set the gravity for
	 *        that element's tooltip to be 'se', preserving the southern
	 *        component.
	 */
	$.fn.tipsy.autoBounds = function(margin, prefer) {
		return function() {
			var dir = {
				ns : prefer[0],
				ew : (prefer.length > 1 ? prefer[1] : false)
			}, boundTop = $(document).scrollTop() + margin, boundLeft = $(document).scrollLeft() + margin, $this = $(this);

			if($this.offset().top < boundTop)
				dir.ns = 'n';
			if($this.offset().left < boundLeft)
				dir.ew = 'w';
			if($(window).width() + $(document).scrollLeft() - $this.offset().left < margin)
				dir.ew = 'e';
			if($(window).height() + $(document).scrollTop() - $this.offset().top < margin)
				dir.ns = 's';

			return dir.ns + (dir.ew ? dir.ew : '');
		}
	};
})(jQuery);
